Switchable Hearing Protection Ear Plug

ABSTRACT

The present invention is a switchable hearing protection ear plug. In one position, the ear plug provides substantial sound attenuation and hearing protection. In the second position, an opening in the ear plug permits sounds to enter the ear of the user relatively unobstructed. A deformable barrier in an interior chamber of the ear plug controls the passage of sound through the ear plug.

RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 61/795,750, filed Oct. 24, 2012.

BACKGROUND OF THE INVENTION

The present invention generally relates to ear plugs for the protectionof human hearing, and more particularly, to a hearing protection earplug that can be easily switched between a position which providessubstantial hearing protection and a second position that permits normalsound transmission.

Resilient foam ear plugs are widely used to provide hearing protection.A cylindrical foam earplug may be compressed and inserted into the earcanal, where it expands and conforms to the ear canal. In its expandedposition, this foam earplug provides a high level of hearing protection.The “foam” used in these ear plugs (and as the term “foam” is broadlyused in this application) can constitute one of many possible softresilient materials, including silicone, neoprene, polyvinyl chloride,polyurethane, and others. Foam ear plugs are effective both as a resultof the sound attenuation properties of the foam and the complete closurethat results from expansion of the foam to contact the entirecircumference of the ear canal. It is important for the effectiveness ofthis ear plug that it remains firmly positioned within the ear canal inits expanded configuration.

Hearing protection is needed in situations such as firearm shootingactivities and industrial settings where there may be periods of loudnoise followed by periods of no noise in which normal conversation isdesirable. With prior art foam ear plugs, however, conversation is verydifficult because of the high level of sound attenuation afforded by theear plug. To permit more normal conversation the ear plug must beremoved, then recompressed and reinserted into the ear canal before loudnoises are again encountered. In any situation in which a user's handsmay become dirty (such as in handling a firearm or in an industrialworkplace setting) the recompression of the earplug for reinsertion intothe ear can result in contamination of the surface of the earplug andtransfer of that contamination to the ear canal of the user.

U.S. Pat. No. 7,182,087 describes a two position hearing protector thatprovides substantial sound attenuation and hearing protection in oneposition, and in a second position allows sounds to enter the ear of theuser relatively unobstructed. That patent describes a mechanicalswitching mechanism for switching the ear plug from the open to closedposition. The present invention is an improvement on the hearingprotector of U.S. Pat. No. 7,182,087 and provides a novel andadvantageous internal mechanism for switching between the soundattenuating and non-sound attenuating positions of the ear plug.

SUMMARY OF THE INVENTION

The present invention is a switchable hearing protection ear plug. Inone position, the ear plug provides substantial sound attenuation andhearing protection. In the second position one or more openings in theear plug permit sounds to enter the ear to the user relativelyunobstructed. Sound passes through an interior chamber in the ear plugand a deformable barrier within the interior chamber either blocks thesound or allows sound to pass through the ear plug to the ear canal ofthe user.

It is an object of this invention to provide a hearing protection earplug that can be easily switched from a position of substantial hearingprotection and sound attenuation to a position of reduced soundattenuation which permits more normal hearing and conversation. Afurther object of this invention to provide a hearing protection earplug that the user does not need to remove in order to carry on normalconversation. Still another object of the invention is to provide acompressible ear plug that conforms to the ear canal of the user butalso permits convenient switching from a position providing substantialhearing protection and sound obstruction to a position of minimal soundobstruction. Still another object of the present invention is to permitswitching between minimal and maximum sound attenuation positions whilekeeping the ear plug fully inserted in the ear canal.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a preferred embodiment of the hearing protection ear plugin the open position in which sounds are minimally attenuated.

FIG. 2 shows a preferred embodiment of the hearing protection ear plugin the closed position in which substantial hearing protection and soundattenuation is provided.

FIG. 3 shows an embodiment of the hearing protection ear plug with analternative deforming actuator.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a preferred embodiment of the hearing protector ear plug 1.The exterior surface of the hearing protector ear plug is ideally madeof a resilient foam or similar material. The foam should be easilycompressible by hand and should return to its original dimensions (orexert pressure against the ear canal of the user) when released. Asshown in FIG. 1, the foam ear plug has a base end 2 that is insertedinto the ear of the user. A deformable barrier 4, in this case sphericalin shape, is located within an interior chamber 8 in the ear plug. Thedeformable barrier 4 is at least partially comprised of foam for desiredresiliency and sound sealing properties. Sound from the exteriorenvironment enters the ear plug through one or more exterior openings 12in the exterior portion of the ear plug 14 (opposite the base end),passes through the interior chamber 8, to one or more sound openings 10in the base end 2. When the ear plug is inserted in the ear of the user,the opening(s) in the base end 10 open into the ear canal of the user.In the embodiment shown in FIG. 1, the size of the deformable barrier 4is selected so that in the open (undeformed) position, there is spacebetween the outer circumference of the deformable barrier 4 and theinner circumference of the interior chamber 8. In this embodiment, thelocation of the sound opening 10 is such that in the open position thereis at least one relatively unobstructed path for sounds to pass from theoutside environment through the ear plug and into the ear of the user.

The exterior portion 14 of the ear plug, with exterior openings 12, maybe a resilient foam, but may also be solid and made of various other,more rigid, materials since it is not critical that this portion form atight seal with the ear canal. It is desirable, however, that theportions with openings contacted by the deformable barrier besufficiently flexible to afford sealing of the openings and providesuitable sound attenuation. The base end 2 of the ear plug must sealwell against the ear canal and should be a properly resilient material.

As shown in FIG. 2, in the closed position, the deformable barrier 4 iscompressed to form a tight seal between its outer circumference and theinner wall of the interior chamber 8, or at least is sufficientlycompressed to block openings 10 and/or 12 to block sound passage throughthe ear plug. The placement of the sound openings 10 and 12 and thedeformable barrier configuration would be a matter of choice to oneskilled in the art. The deformable barrier 4 could be of various shapesthat accomplish the same objectives. Preferably, however, the deformablebarrier 4 and the interior chamber 8 would be essentially spherical andcylindrical, respectively.

FIGS. 1 and 2 show a deforming actuator 16 that presses against thedeformable barrier 4 to cause its deformation. The deformable actuator16 shown in FIGS. 1 and 2 can be similar to the mechanism in U.S. Pat.No. 7,182,087. When the exterior end 18 of the actuator is pressed, theinterior piston 20 of the deforming actuator moves further into theinterior chamber and deforms the deformable barrier 4 so that it blocksopening 10. The internal components of such an actuator are similar tothose described in U.S. Pat. No. 7,182,087 and would be known to oneskilled in the art. Switching based on pressure applied against theexterior end of the ear plug (pressing the ear plug in the direction ofthe ear of the user and thereby causing the ear plug to remain in placein the ear) is preferable over a switching force that tends to pull theear plug out of the ear. In an alternative embodiment, various meansavailable to one skilled in the art could be used to reduce the volumeof the interior chamber and thereby cause suitable deformation of thedeformable barrier.

In a preferred embodiment, the exterior portion 14 and base end 10 ofthe ear plug would be substantially integrated with an integral flexiblefoam portion between them defining the interior chamber, so that fromthe outside the ear plug would appear to be a uniform ear plug much likethe typical one piece foam ear plugs. Other, less uniform, approacheswould also be acceptable.

Proper sizing of the deformable barrier 4 is critical. Given the smalldesired size for the ear plug ear plug, the ideal spherical deformablebarrier would ideally have an uncompressed diameter of between about ⅛and ⅜ of an inch. The deformable barrier may be solid foam or a solidfoam filled with a fluid. The material used for the deformable barrier(or its filling) may be selected from a range of foam, rubber andpolymer products that have suitable properties of rebound resilience anddurometer hardness. The deformable barrier should properly seal thesound opening(s).

Other mechanisms for switching the ear plug between the open and closedpositions may be used. FIG. 3 shows a deforming actuator that utilizes amoveable cam 22. In the closed position the cam 22 deforms thedeformable barrier 4 and blocks the passage of sound through openings10. Movement of the cam lever 24 would be based on force either in thedirection of the ear or at least perpendicular to that direction so thatlever movement should not tend to pull the ear plug out of the ear. Abiasing force within the ear plug may be desirable to move the deformingactuator into a second position (either open or closed) so that auser-applied force away from the ear would not be needed, That biasingforce may also be exerted by the deformable barrier as a result of itscompression, as in the case of the actuator shown in FIG. 3. In such aconfiguration, it is desirable to use the deformable barrier as both thebiasing means and as the means for blocking sound passage.

The number of sound openings in the base end 10 and the number ofopenings in the exterior portion 12, and their locations, are matters ofchoice to one skilled in the art. A suitable configuration wouldhowever, require blocking of all openings in either the base end or theexterior portion to block sound transmission in the closed position.

Other desirable approaches to switching between ear plug positions wouldinclude opening and closing with a twisting motion. Such a twistingclosure could involve, for example, rotating a threaded exterior earplug portion or twisting the exterior end to engage a locking tab tolock the ear plug either open or closed against a biasing force. Stillother switching approaches would be easily utilized by one skilled inthe art.

While the embodiments shown are in the closed position when thedeformable barrier is substantially deformed and open when thedeformable barrier is substantially undeformed, alternative oppositeconfigurations would also be possible. In the opposite configurationsounds are blocked when the deformable barrier is in the substantiallyundeformed state, and sounds are transmitted when the deformable barrieris substantially deformed (and at least one each of openings 10 andopenings 12 are unobstructed). In such an opposite configuration theopenings 10 into the base end could be located nearer the exterior end14 of the ear plug so that they would be blocked by a substantiallyundeformed deformable barrier, and not blocked when the deformablebarrier is deformed by force in the direction of the base end 2.

I claim:
 1. A hearing protection ear plug comprising: a base end, aportion of which fits in the ear of a user, an interior chamber, atleast one opening passing through the base end into the interiorchamber, at least one opening passing from the interior chamber to theexterior of the ear plug, and a substantially spherical deformablebather within the interior chamber.
 2. The ear plug of claim 1 whereinwhen said deformable barrier in a substantially deformed state sounddoes not pass from said opening in the base end through the interiorchamber to the opening in the exterior of the ear plug, and when saiddeformable barrier is in a less deformed or un-deformed state, soundpasses from said opening in the base end through the interior chamber tothe opening in the exterior of the ear plug.
 3. The ear plug of claim 1wherein said interior chamber is substantially cylindrical and saiddeformable barrier and has an undeformed diameter less than the interiordiameter of the substantially cylindrical interior chamber.
 4. The earplug of claim 1 further comprising a deforming actuator that in one ofat least two positions deforms the deformable barrier and in anotherposition does not deform the deformable barrier or deforms it to alesser extent.
 5. The ear plug of claim 4 wherein said deformingactuator is activated by force exerted in the direction of the base endof the ear plug.
 6. The ear plug of claim 4 wherein said deformingactuator is activated with a rotational force.
 7. The ear plug of claim4 wherein said deforming actuator comprises an interior piston thatmoves into the interior chamber and deforms the deformable barrier. 8.The ear plug of claim 4 wherein said deforming actuator is the interiorsurface of the interior chamber.
 9. The ear plug of claim 4 wherein saiddeforming actuator causes a reduction in the volume of the interiorchamber.
 10. The ear plug of claim 4 wherein the deformable barrierprovides a biasing force to the deforming actuator. 11-20. (canceled)